title: Interaction between whole buttermilk and resveratrol.
abstract: The interaction between buttermilk and resveratrol (trans-3,5,4'-trihydroxystilbene) was examined using fluorescence spectroscopy. Ultracentrifugation of buttermilk (10% total solids, TS)-resveratrol (100-1600 μM) mixtures yielded three fractions comprising cream (14.79% w/w, 1.12% TS), milk serum (75.94% w/w, 5.56% TS), and a casein-rich precipitate (9.27% w/w, 2.94% TS). The majority of the added resveratrol was partitioned into the casein-rich precipitate (50.5-56.8%), with lesser amounts in the milk serum (35.3-41.2%) and cream layer (7.9-8.7%), demonstrating that most of the resveratrol interacted with the proteins. The interaction of the milk proteins with resveratrol was investigated by measuring the quenching of protein intrinsic fluorescence. Complex formation was spontaneous and exothermic. The apparent binding constants between milk proteins in buttermilk and resveratrol were ≥ 2.47 × 10(4), 1.65 × 10(4), 1.11 × 10(4), and 0.72 × 10(4) M(-1), respectively, at 278, 288, 298, and 308 K. The increased aqueous solubility of resveratrol by complexation to whole buttermilk makes it useful as a food vehicle for carrying resveratrol.
authors.affiliation: CSIRO Preventative Health National Research Flagship and CSIRO Animal, Food and Health Sciences, 671 Sneydes Road, Werribee, VIC 3030, Australia.
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Ye
authors.forename: Emilie
authors.initials: E
authors.lastname: Thomas
authors.forename: Luz
authors.initials: L
authors.lastname: Sanguansri
authors.forename: Yue-Rong
authors.initials: YR
authors.lastname: Liang
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Augustin
mesh_terms: D002364:Caseins / Q000737:chemistry; D043302:Cultured Milk Products / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry; D008894:Milk Proteins / Q000737:chemistry; D000077185:Resveratrol; D013050:Spectrometry, Fluorescence; D013267:Stilbenes / Q000737:chemistry*; D013816:Thermodynamics; D014461:Ultracentrifugation
chemical_list: D002364:Caseins; D004337:Drug Carriers; D008894:Milk Proteins; D013267:Stilbenes; D000077185:Resveratrol